Threading-machine



F. MULLER.

THREADING MACHINE.

APPLICATION FILED FEB. 15, I918.

Patented July 27, 1920.

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F. MULLER.

THREADING MACHINE.

APPLICATION FILED FEB. I5 l9l8.

Patented July 27, 1920.

6 SHEETS-SHEET 3.

F. MULLER.

THREADING MACHINE.

APPLICATION FILED FEB. 15, I918.

Patented July 27, 1920.

6 SHEETS-SHEET 4.

INVENTOR U. H. J

F. MULLER.

THREADING MACHINE.

APPLICATION FILED FEB. 15. I918.

Bailya R/VEY F. MULLER.

THREADING MACHlNE.

APPLICATION FILED FEB. 15. l9l8.

1,347,788. Patented July 27, 1920.

6 SHEETS-SHEET 6.

UNITED STATES PATENT OFFICE.

FRIEDERICH M'U'LLER, OF HARTFORD, CONNECTICUT, ASSIGNOR TO PRATT 8a WHITN'EY COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NE JERSEY.

THREADING-MACHINE.

Specification of Letters Patent.

Application filed February 15, 1918. Serial No. 217,321.,

will be understood that the invention is not limited to tap threading machines and that many of the features of the invention can be equally well applied to machines adapted for other threading or cutting operations.

()ne of the objects of the invention is to provide an automatic machine having improved features of construction and operation whereby it is adapted to automatically supply blanks from a magazine, automatically thread the blanks and automatically discharge them. Another object of the invention is to provide improved threading mechanism adapted to cooperate with the turret and to thread blanks carried thereby. Still another object of the invention is to provide means whereby the operation of the threading or similar mechanism is initiated by the mechanism which effects the indexing and the supply and discharge of blanks, and whereby the operation of the mechanism which effects the indexing and the supply and discharge of blanks is initiated by the threading mechanism. An additional object of the invention is to provide improved operating mechanism whereby the several parts of the machine are operated and controlled in correct relationship. btill further objects of the invention will be apparent from the following specification and claims.

The accompanying drawings show the embodiment of the invention which is now deemed preferable, but it will be understood that various changes and substitutions of equivalents can be made without departing from the spirit of the invention as set forth in the claims forminga part of this specification.

Of the drawings:

Figure l-is a plan view of a machine embodying the invention.

Fig. 2 is a front elevation, certain parts Patented July 27 1920.

being broken away and others shown in section along the line 2-2 of Fig. 1.

Fig. 3 is a longitudinal sectional view taken along the line 33 of Fig. 1.

Fig. 4 is an end View taken from the right, as shown by the arrow of Fig. 1'.

Fig. 5 is a fragmentary sectional view taken along the lines 5-5 of Figs. 1 and 4. Fig. is a fragmentary transverse sectional view taken along the line 6-6 of Fig. 1.

Fig. 7 is tional view taken along the line 7-7 of Fig. 1. In this view the cutters in one of the cutter heads are omitted.

Fig. 8 is a fragmentary transverse sectional view taken along the line 8-8 of Fig. 1, parts of the turret being also shown in section.

Fig. 9 is an enlarged face view, partly in section, of one of the cutter heads, some of the cutters being removed. Fig. 10 is a fragmentary longitudinal sectional view taken along the lines 10-10 of Fi s. 7 and 9.

ig. 11 is a fragmentary horizontal sectional view taken along the line 1111 of F ig. 7.

he machine has a work-carrying turret which is rotatable about a longitudinal horizontal axis. As shown in Figs. 1 and 2, the turret comprises a head 1 which is securely mounted upon a trunnion 2 at the left-hand end thereof. The trunnion is relatively long and is rotatably mounted in a bearing 3 formed in a bracket 4; extending upward from the main frame 5.

The turret head 1 includes a cover 6 which is suitably secured in place. Rotatably mounted in the head 1 are several work-carrying spindles 7 four such spindles being provided in the present instance. The spindles are mounted with their axes parallel to the axis of the trunnion 2 and they are equally spaced circumferentially and are positioned at equal distances from the axis of the trunnion as shown most clearly in Fig. 3, each spindle is mounted in bearings 8 and 9 formed in the body of the head and in the coverrespectively.

Mechanism is provided for driving the spindles, this preferably comprising spur gears 10 secured respectively to the spindles in the space between the body of the head and the cover. The four spur gears 10 all mesh with a central spur gear 11 which is driven by a shaft 12 concentric with the trunnion 2. Preferably the trunnion 2 is in the form of a hollow shaft and the shaft 12 extends through and has a bearing in the central aperture thereof. Near the righthand end of the shaft 12 there is a driving vdevice preferably a sprocket wheel 13.

, wheel 18 in register with the sprocket wheel 13 on the shaft 12. A sprocket chain 18 engages these two sprocket wheels and serves to transmit power from the shaft 15 to the shaft 12. In this way the four spindles T are continuously driven.

As shown most clearly in Fig. 3, each spindle 7 is provided at its outer end with a collet chuck 19 which is adapted to be opened and closed by means of a longitudinally movable sleeve 20 positioned within the spindle. Secured to the right-hand end of the spindle is a collar 21 which carries two pivotally mounted knuckle levers 22, 22. The inner ends of these levers abut against a projection 23 on the end ofthe sleeve 20 and the outer ends of the levers are engaged by a cam surface formed on an annularly grooved collar 24 slidable along the spindle. It will be clear that when the collar 24 is moved toward the right the levers 22, 22 will be swung outward to force the sleeve 20 toward the left and thus close the chuck to engage a blank. \Vhen the collar 24 is moved toward the left, the sleeve 20 is permitted to move toward the right and the chuck is permitted to open to release the blank.

I provide means whereby the turret is automatically indexed from time to time so that each spindle is moved successively to several operating positions or stations, there being four such stations when there are four spindles, as herein shown and described. In

operation, blanks are supplied to the spindles as they successively reach one station; at the two successive stationscutting operations are effected upon the blanks; and at the fourth station the completed blanks are ejected or discharged. The mechanism for bringing about these several results will be fully described hereinafter and for the present I will confine myself to a description of the mechanism whereby the indexing is'effected.

For operating the indexing mechanism (and for effecting other results as will presently appear) the machine is provided with a longitudinal rotatable shaft 25 which is preferably positioned as shown, directly) below the shaft 12. liounted on the shaft 25 is a worm wheel 26 which meshes with a worm 27 connectible with a transverse horizontal shaft 28. At the front-end of the shaft 28 there is secured a bevel gear 29 which meshes with a bevel gear 30 on a longitudinal horizontal shaft 31. This shaft 31 is mounted in bearing brackets 32, 32 carried by the main frame and has secured to it a belt pulley 33 in register with the aforesaid belt pulley 17 on the shaft 15. A belt 34 engages these two pulleys and thus serves to continuously rotate the shaft 31 and through it the shaft 28. By means of the worm and worm wheel the shaft 28 drives the shaft 25. Suitable means, to be more fully described hereinafter, is provided for causing the rotation of the shaft 25 to be intermittent, the shaft preferably moving through one complete revolution at the con clusion of each threading or cutting operation.

At the right-hand end of the shaft 25, as

shown in Fig.4, there is mounted a disk 35 which is provided with a cam groove 36. Preferably, for convenience of construction, this cam groove is formed by means of separate plates 37 and 38, which are secured to the disk 35. Pivotally mounted on the main frame at 39 is a lever 40 which is provided at 41 with a roller which enters the cam slot 36. To the opposite end of the lever 40 there is pivotally connected a link 42 which is used for effecting indexing in the manner.

to be described.

Secured to the trunnion 2 at the righthand end, as shown in Fig. 5, is a hub 43 to which is fixed a locking disk 44. Rotatably mounted on the hub is an indexing disk 45. Secured to the hub 43 adjacent the disk 45 is a ratchet wheel 46 having as many ratchet teeth 47 as there are spindles, four in the present instance. The upper end of the aforesaid link 42 is pivotally connected at 48 to the disk 45 and the result is that the disk 45 is oscillated through an angle of approximately 90 when the shaft 25 and the cam disk are. turned. The disk 45 carries a pivoted spring pressed pawl 49 which is adapted to engage one of the teeth 47 It will therefore be clear that when the disk 45 is oscillated one of the teeth.

47 will be engaged by the pawl and the wheel 46 will be rotated through an angle of approximately 90, carrying the trunnion and the turret with it. The cam groove 36 is so shaped that the disk 45 is held stationary during a considerable part of the rotation of the disk 35; then the lever 40 is moved relatively slowly upward to turn the disk 45 in the indexing direction; and finally the lever 40 is swung relatively quickly downward to return the disk 45 to its initial position.

In order that the turret may be locked in a definite position after each indexing operation, the aforesaid plate 44 is provided with notches 50 adapted to be engaged by a latch 51 which is horizontally slidable in a suitable bracket 52. A spring 53 normally pushes the latch toward its operative position. Pivotally mounted at 54 on the disk 45 is a cam dog 55' having a cam surfaceat 56. This cam surface is adapted to engage a pin 57 carried by the latch 51. As shown in Fig. 4, the indexing mechanism is so adjusted that normally the pawl 49 lies a slight distance from the tooth'47 which is to be engaged. Therefore when the disk slide 60.

45 is moved the first result is the engagement ofthe cam surface 56 with the pin 57, thus moving the latch 51 toward the left and out of engagement with the disk 44.

By the time the latch is disengaged from the disk the pawl 49 engages the tooth 47 and turns the turret through an angle of 90, as

already described. When the cam surface Fig. 8. This slide is provided with an arc- I uate flange 61' which lies in planes perpendicular to the axis of the turret and which 1s concentric with the said axis. This flange is adapted to project into the annudrical surface 64 fitting an aperture in the At the lower end of the shaft 62 is a gear 65 which meshes with teeth 66 at the rear end of a lever.67. This lever is pivoted at 68 for movement about a vertical axis and at its inner end is provided with a roller- 69 which is adapted to be engaged by cams 70 and 71 on a cam drum 72 carried by the shaft 25.

The cam 7 0 engages the roller 69 almost 56 of the dog has moved past the pin 57 the immediately after the starting of the shaft latch 51 is engaged with the edge of the disk 25 and moves the lever 67 in the counter- 44 under the pressure of the spring 53. As clockwise direction thus moving the arm 63 soon as the next notch 50 reaches the latch and the slide 60 toward the left from the the latch snaps into it and thus firmly locks position shown. In this way the collar 24 the turret in its new position. As the disk 45 is moved backward the dog 55.swings outward about its pivot 54 so as to pass the pin 57. Preferably, as shown, the disk 45 carries a projection 58 which serves to support the dog 55 and hold it against lateral movement.

The disk 35 is so positioned on the shaft 25 that at the end of each movement-of the shaft the disk occupies approximatel the position shown in Fig. 4. This positlon is maintained during the threading or cutting operation, and at the end of this operation the rotation of the shaft 25 is started. The roller 41 is at or near the beginning of the circular part of the cam groove so that indexing will not occur until the shaft 25 has made a part of a revolution.

Almost immediately after the shaft 25 begins to rotate the chucks at the two rear stations are opened to permit a new blank to be inserted at the first station and to permit a previously finished blank in the fourth station to be ejected. For opening the chucks the following mechanism is provided.

A bracket 59 projects upward from the main frame of the machine at the rear. This bracket is relatively long as shown in Figsyl and 3, preferably extending from a point at the right-hand end of the machine to a point beyond the center. The bracket is provided with a longitudinal horizontal guideway which extends throughout'the en tire length.

A slide 60 is mounted in the longitudinal guideway in the bracket 59, as shown in is moved toward the left, permitting the levers 22, 22 to swing. inward and thus open the chuck.

I provide means whereby blanks to be threaded or out are automatically fed to the blank-holding spindles. Preferably, as shown, the supplying or magazine -mechanism is associated with the upper rear station of the turret. I

As illustrated in Figs. 1, 3 and 7, there is provided at the rear of the machine an upward extending bracket 73 having a vertical slideway in which is fitted a slide 74. This slide can be vertically adjusted by means of a screw 75 and can be locked in adjusted position by means of bolts 76. Secured to the slide 74 at its upper end is a plate 77 which is inclined at an angle of approximately 45 and which forms the main frame of the magazine mechanism. At one end of the plate 77, preferably the ri ht-hand end, there is located an angle bar 8, one leg 79 of which overhes and is parallel to the plate 77 and the other leg 80 of which engagesthe end surface of the plate. The leg 80 is provided with slots 81 which are inclined.

at angles of approximately 45 to the longitudinal lines of the bar and are there fore approximately vertical, as shown in Fig. 7. Bolts 82 project from the end of the plate 77 throu h these slots. This construction permits 1; e angle bar 78 to be adjust-ed toward or away from the plate 77, and by means of the nuts on the bolts 82, the angle bar can, be locked in adjusted positioni1 Preferably there is a rail 83 secured to t e plate 77 adjacent the angle bar 78. 13(

The rail 83 and the upper leg 79 of the angle bar coiiperate to form a runway or guideway for the right-hand ends of the blanks to be operated upon.

Longitudinally adjustable along the plate 77 is an angle bar 81 adapted to be secured in place by means of bolts 85 having heads which enter dovetailed slots 86 extending longitudinally of the plate. The vertical leg 87 of the angle bar 81 is provided with slots 88 which are inclined at an angle of 15 with respect to the longitudinal lines of the bar and which are therefore approximately vertical. Adjacent the said leg 87 is a second angle bar 89 having a leg 90 parallel to the plate 77. The vert cal leg of the angle bar carries bolts 91 which project through the aforesaid slots in the angle bar 87. This construction permits the angle bar 89 to be adjusted and it can be locked in adjusted position by means of the nuts on the bolts. Preferably there is a rail 92 secured adjacent the angle bar 8i and this rail. in cooperation with the bottom leg 90 of the angle bar 89. forms a guidewayor runway for the left-hand ends of the blanks to be operated upon.

It will be seen that by moving the bar 84: longitudinally of the plate the magazine mechanism may be adjusted for blanks of different lengths. It will further be seen that by moving the angle bars 78 and 89 upward or downward the magazine may. be adjusted for blanks of different diameters.

As shown in Fig. 7, a longitudinal strip 93 is secured to the bottom of the plate 77, and this strip forms a stop for the lowermost blank in the magazine runway. The strip 93 is so positioned that the said lowermost blank is held with its axis in the same vertical plane as the axis of the work spindle at the upper rearmost station. Obviously the vertical position of the axis of the blank with respect to the magazine will vary with blanks of different diameters; but. by means of the aforesaid screw 75, the entire magazine mechanism may be raised or lowered to bring the axis of the blank into exact alinement with the axis of the spindle. I

For moving a blank from its lowermost position in the magazine into the chuck at the supply station, I provide a longitudinally movable rod 94. This rod is carried by a slide 95 which is longitudinally movable in a suitable guideway in the main frame. Preferably the rod 94 is capable of a slight longitudinal movement with respect to the slide, being held in its extreme relative right-hand position by means of a coil spring 96. For moving the slide 95 I pro vide a lever 97 which is connected to a pivot pin 98 mounted on the main frame and which has at its upper end a cylindrical surface 99 fitting a suitable aperture in the 25. The cam, 102 is so positioned that it engages the roller 101 to swing the levers 100 and 97 in the clockwise direction almost immediately after the chucks 19 have been opened by the cam as already described. This movement of the levers moves the slide 95 toward the right and the rod 941 engaging the lowermost blank in the magazine, pushes it. toward the right 'into the corresponding chuck, which is open in time to recelve it.

Preferably bearing brackets 105, 105 are secured to the ends of the plate 77, and these carry a longitudinal rock shaft 106. Adjnstably secured to this rock shaft is an arm 107 carrying a finger 108 which is adapted to extend into the blank space and to support the blanks'therein. The slide 95 is provided with a cam 109 which engages an arm 110 carried by the rock shaft 106. This cam 109 moves the arm 110 and thus turns the rock shaft in the direction to force the finger 108 between the lowermost blank and the next one, thus supporting the second blank and those above it while the lowermost blank is being moved into the chuck. hen the slide 95-moves backward toward the left the finger 108 is withdrawn and the blanks are permitted to move downward under the action of gravity.

Slidably supported within the sleeve 20 of each spindle is a stop and ejector rod 111, the rear end of which extends approximately to the end of the spindle. This rod serves to limit the movement of the blank into the chuck, and for properly positioning the rod the following mechanism is provided.

A slide 112 is mounted in the guideway in the bracket 59 at the right-hand end thereof and is provided with a bracket 113 which projects diagonally upward toward thefront and which carries a rod 114 in alinement with the rod 111. This rod 114: is adjustable in the bracket 113 and can be held in adjusted position by means of a set screw 115. Rotatably mounted in bearings formed on the bracket 59 is a vertical shaft 116 which carries at its upper end an arm 117. This arm extends forward and is provided with a. cylindrical surface 118 which fits an aperture in the slide 112. At the lower end of the shaft 116 is a gear wheel 119 which meshes with gear teeth 120 at the rear end of a lever 121. This lever is pivoted at 122 for movement about a vertical axis and at its front end is provided with a roller 123 which is positioned to be engaged by cams 124 and 125 carried by a cam drum 126 on the shaft 25. The cam v right.

*left the rod 114 engages the rod 111 and operations, the machine, as stated,

124 is so positioned that it swings the lever 121 in the counter-clockwise direction and thus moves the arm 117 and the slide 112 toward the left at approximately the same time that the slide 95 is moved toward the As the slide 112 moves toward the pushes it toward the left in position to serve as a stop for the blank which is being pushed into place by the rod 94. The rod 111 serves to limit the innermovement of the blank and the rod 94 yields against the action of the spring 95, thus firmly holding the blank in a definite predetermined position.

At the same time that a new blank is being supplied at the first station a previously finished blank is being ejected from the fourth station. For ejecting the finished blank the slide 112 is provided with a bracket 127 which extends diagonally downward toward the front and carries a rod 128 in alinement with the rod 111 at the discharging station. T he rod 128 is longitudinally adjustable and can be held in adjusted position by means of a set screw 129. The movement of the slide 112 toward the left, as already described, moves the rod 111 at the discharging station toward the left and ejects the finished blank.

When a new blank has been supplied at the first station, as described, the cam .71 engages the roller 69 to swing the lever 67 in the clockwise direction and move the slide toward the right, thus closing the chuck. This movement of the slide also closes the chuck at the fourth station, but that is immaterial as the blank has already been ejected.

When the chuck at the first station has been closed the cams 102 and 125 respectively engage the rollers 101 and 123 thus effecting the movements necessary for the withdrawal of the rods 94 and 114.

By the time when the supplying and discharging operations have been completed, the continued rotation of the shaft 25 has turned the cam disk 35 so that the inclined part of the cam 36 is ready to engage the roller 41. Then indexing takes place in the way already described. The shaft 25 stops with the several cams in the positions shown in the drawings.

Mechanism is provided for operating upon the blanks at the two front stations, and, for purposes of illustration, I have shown mechanism for performing threading eing primarily intended for threading purposes. At the first operating station a roughing cut is taken to partly form the thread and at the second operating station a finish cut is taken to finish the thread.

Both sets of threading devices or tools,

Q. which will hereinafter be described in de.

that the threading devices are moved in the operative direction at a speed which is definitely related to the speed of rotation of the spindles so that the threads may be accurately pitched. As illustrated, the mechanism comprises a longitudinal rotatable shaft 134 which is provided with threads a threaded projection 135 on the engaging slide 130. Mounted in alinement with the shaft 134 is a shaft 136 carrying a clutch element 137. An annularly grooved clutch collar 138 is splined to the shaft 134 and is provided at one side with a tooth adapted to engage the tooth of'the clutch element 137. When the clutch collar is in its righthand position the shaft 134 is connected with the shaft 136 to be driven thereby. The shaft 136 is rotated continuously in timed relation with the rotation of the spindles 7 and preferably receives power directly from the shaft 12. As illustrated, the shaft 12 carries a gear 139 which meshes with a gear 140. The gear 140 is mounted on a stud 141 which is carried by a plate 142. Also mounted on the stud 141 and connected with the gear 140 is a pinion 143 which meshes with a gear 144. The gear 144 is mounted On a stud 145 which is adjustable in an arcuate slot 146 formed in the plate 142. Also mounted on the stud 145 and connected with the gear 144 is a pinion 147 which meshes with a gear 148 secured to the shaft 136. By means of this gearing the shaft 136 is driven continuously and at a speed definitely related to the speed of rotation of the spindles. When the clutch collar 138 is in its right-hand position the shaft 134 is rotated relatively slowly with the shaft 136, the direction of rotation being such that the slide 130 is moved in the operative direction, that is, toward the right. By removing one or more of the gears 143, 144 and 147 and substituting other gears with different diameters, the speed ratio between the spindles and the shaft 134 can be changed. In practice the proper gears are selected to turn the shaft 134 at a rate such that the movement of the slide will correspond exactly to the required pitch of the threads to be cut on the blanks carried by the spindles.

Rotatably mounteji on the shaft 134 is a sleeve 149 carrying spiral gear 150. This spiral gear meshes with a spiral gear 151 secured to the aforesaid shaft 28. The sleeve 149 is provided with clutch teeth adapted to be engaged b similar teeth on the clutch collar 138. The sleeve 149-is driven continuously from the shaft 28 and in the direction opposite to the direction of rotation of the shaft 136. Therefore, when the clutch collar 138 is in its left-hand position, the snaft 134 is driven relatively rapidly in the direction to return the slide 130, that is, to move it toward the left.

For moving the clutch collar 138 there is provided a forked lever 152 which is pivoted at 153. The lever has a de ending portion 154 carrying a pin 155. ounted on the cam disk 35 are three cam members or tappets 156, 157, 158. The clutch collar 138 is shown in its right-hand position, which is the position for threading. At the end of the threading operation the pin 155 is engaged by the tappet 157 which moves the pintoward the right, thus moving the clutch collar toward the left and disconnecting the shaft 134 from the shaft 136 and connecting it with the sleeve 149. The slide 130 is thus moved rapidly toward the left and the threading tools are withdrawn. This movement continues until the tappet 158 engages the pin 155, whereupon the clutch collar 138 is moved to central neutral position, and the movement of the slide 130 is stopped. The tappet 158 is adjustably secured to the disk 35 so that it can be adjusted in accordance with the required movement of the slide. Obviously the backward movement must be varied in accordance with the length of the thread being cut on the blanks. After being moved to neutral position the clutch collar remains in that position during the operation of the mechanism which effects the supply and discharge of blanks and which effects indexing.

After the ejection of the finished blank and the su plying of a new one and after indexing, t e pin 155 is engaged by the tappet 156 which moves the pin toward the left and thus movesthe clutch collar 138 toward the right into engagement with the clutch element 137 onthe shaft 136. Then the shaft 131 is rotated slowly in the direction to move the slide 130 in the operative direction, that is, toward the right.

Preferably, for resiliently holding the clutch collar in its neutral position, the lever 154 is provided with a boss 159 having a notch which is entered by the pointed end of a lever 160. A spring 161 serves to press the'lever 160 downward. r

As already stated, the mechanism which moves the slide 130 is entirely disconnected from the driving devices during the operation of the mechanism which effects the supply and discharge of blanks and which effects indexing. Preferably I provide means whereby the latter mechanism is entire y disconnected from the driving devices during the operation of the mechanismwhich moves the threading devices in the operative direction. I provide means whereby each of these mechanisms serves, after completing its cycle of operations, to stop itself and to start the operation of the other mechanism.

Inthis respect a machine embodying my present invention, while different in detail, is similar in principle to the mechanism set forth in my copending application for driving mechanism, Serial No. 198,058, filed October 23rd, 1917 as a division of my earlier application for tap making machine, Serial No. 607,420, filed February 8, 1911 and renewed October 23rd, 1917 as Serial No. 198,185.

The aforesaid worm 27 is not secured to tends to move the clutch collar 162 into engagement with the clutch tooth carried by the shaft 162. When the clutch collar 162 is in its rearmost position, as shown in Fig.

6, the worm 27 is rotated and serves to rotate the worm wheel 26 and the shaft 25 in the direction indicated by the arrow. The worm wheel 26 carries a pin 166 which is adapted to engage a finger 167 secured to the rod 163. When the shaft 25 has made a complete revolution, the pin 166 engages the finger 167 and moves the rod 163 toward the front, thus disengaging the collar 162 from the worm 27 and stopping the rotation of the worm and of the Worm wheel and of the parts connected therewith.

, As shown in Figs. 2 and 6, the rod 163 at its front end has secured to it a collar 168 having a projection which is-engaged by a pivoted lever 169. A longitudinal rod 170 is slidably mounted on the main frame and engages the lever 169. A bolt 171 has threaded engagement with the slide 130 and is mounted in alinement with the rod 17 0. When the slide 130 has nearly completed its movement in the threading direction, the

head of the bolt 171 engages the rod 17 0 and swings the lever 169. The movement of the lever 169 serves to turn the rod 163 in the clockwise direction. This rotative movement of the rod 163 serves to disengage the finger 167 from the pin 166 whereupon the spring 165 moves the rod toward therear and carries the "clutch collar 162 into engageme t with the shaft 162. This starts the rotation of the worm 26 and of the shaft pleted its forward movement has caused the disengagement of the finger 167 from the pin 66 and the rotation of the shaft'25 is about to start. The tappet 157 is in position to engage the pin 155 and start the return movement of the slide as already described. After the return movement the slide is entirely disconnected from the power devices. The tappet 156, which starts the forward feeding movement of the slide 130, is positioned to act just before the rotation of the shaft 25 and of the several cams carried thereby, is stopped. This feeding movement once having been started continues until the slide 130 again starts the rotation of the shaft 25 and of the cams. This cycle of operations is repeated indefinitely.

The threading mechanism preferably comprises two cutter heads which are mounted respectively in alinement with the spindles at the two front stations, that is, stations two and three. The heads are provided with chasing cuttersadapted to engage the rotating blanks.

Projecting upward from the slide 130 is a bracket 172. This bracket is provided with longitudinal apertures respectively'in alinement with the front spindles, and in each of these apertures there is positioned a trunnion 173 which is normally held against rotation. Connected to each trunnion is a plate 174 having radial guideways 175. Movably mounted in each of the guideways is a slide 176, and preferably each slide carries a block 177 which is radially adjustable independently of the slide under the control of a screw 178. Carried by the block 177 is a chasing cutter 179 which is adjustable with respect to the block by means of a screw 180.

Rotatably mounted on the trunnion 173 is a worm wheel 181 and connected with the worm wheel is a hub in which cam grooves 182 are formed. Each of the slides 176 carries a roller 183 which enters one of the cam grooves 182. From the foregoing description it will be obvious that when the worm wheel 181 is turned, the slides 176 with the cutters will-be moved radially in- 188 carried by the slide 185. The plunger is pressed into operative position by a coil spring 189.

Mounted on the slide 186 are two vertical rotatable worms or screws 190,190 which mesh respectively with the worm wheels 181, 181. Each of the worms 190 is provided with a squared end whereby it may be turned to turn the corresponding worm Wheel and adjust the cutters of the corresponding cutter head inward or' outward.

Each worm after adjustment may be clamped in adjusted position by means of a screw 191. The two worm wheels 181, 181 may be turned simultaneously by moving the slide 186, either with the slide 185 or independently thereof. During such movement the worms 190, 190 serve as racks for turning the worm wheels 181 which act as spur gears. v

It will be understood that the cutters 179 are constructed with teeth corresponding in form and'pitch to the threads to be cut on the blanks. By means of the screws 178 and 180 the cutters of each head are adjusted so as to lie at equal distances from the axis and, by means of the corresponding worm 190, all of the cutters are moved inward or outward in accordance with the diameter of the blanks. The cutters on the upper head are adjusted so as to partly cut the threads, whereas the cutters on the lower head are adjusted to a slightly smaller diameter so as to finish the threads which were partly cut during the preceding operation by the cutters on the upper head.

WVhen the slide 130 is moved in the cutting direction toward the right, as already described, the cutters of the two cutter heads respectively engage the blanks carried by the spindles at the second and third stations. Threads are cut on the blanks, the upper cutters taking a roughing out and the lower cutters taking a finishing cut. As already pointed out, the slide 130 is positively geared with the spindles so that the rate of movement is definitely related to the rate of spindle rotation. In this way I secure an accurate pitch of the threads, this being impossible with threading devices in which the longitudinal movement of the cutters is entirely dependent upon their own engagement with the blank.

In threading taps it is preferable to move the cutters inward slightly during the cutting operation so that the upper or inner part of the thread will have a diameter very slightly less than the end part. To accomplish this result I provide means for moving the slides during the cutting operation. As shown, the slide 185 carries a block 192 which has a notch into which projects a plate 193 carried by the main frame. This plate 193 is very slightly inclined do nward to t e r g incl nation being greatly exaggerated in Fig. 2. The result is that, as the slide 130 1s moved toward the right, the slide 185 is moved down-.

ward, carrying the slide 186 and the worms 6 190, 190 with it and thus moving the cutters inward. lVhen the slide 130 is moved backward the operation is reversed and the cutters are restored to their original positions. The springs 184 serve, during this 10 movement aml during other movements to be described, to take up all lost motion and to hold the cutters in the outermost positions which the adjustment of the several parts permits. At the end of the forward cutting movement the slide 130 acts, as already described, to start the cam shaft 25, whereupon the tappet 157 stops the forward movement of the slide and starts it in the reverse direction by throwing the clutch 138 from its right-hand position to its left-hand posi' tion. It will be obvious that the cutters must be separated from the blanks before they can be moved backward. For open- 26 ing the heads to separate the cutters the following mechanism is provided: A coil spring 194 is interposed between the slides 185 and 186 and serves to apply an upward pressure to the slide 186. Normally the 30 plunger 187 prevents the slide 186 from moving upward under the action of the spring. Slida-bly mounted in the bracket 172 is a transverse horizontal rod 195. This rod extends through a vertical slot in the slide 185 and abuts at its front end against the plunger 187. Pivotally mounted on the main frame at 196 is a lever 197 which is adapted at its upper end to engage the rod 195. The lower end of the lever 197 is provided with a. roller 198 which is positioned to be engaged by cam plates 199 and 200, secured to the end of the cam drum 104. The cam plate 199 is so positioned that simultaneously with the stopping of the forward movement of the slide 130 it engages the roller 198 to swing the lever 197 in the counter-clockwise direction. The lever moves the rod 195 toward thefront, thus moving the plunger 187 out of engagement 60 with the slide 186. Immediately the slide is moved upward by the spring 1.94, thus turning the worm wheels 181 and moving the cutters outward. The cam plate 200 restores the lever 197 to the position shown in Fig. 7.

The slide 186 extends downward through a slot in the slide 130 and is provided at its lower end with a horizontal ledge 201. A lever 202 is pivoted to the main frame of the machine at the rear as indicated at 203. At the front end of the lever is a roller 204 which is positioned to be engaged by cam plates 205 and 206 carried by a cam disk 207 on the cam shaft 25. The lever .5 is provided between its ends with a hook member 208 which is adapted to engage the ledge 201 on the slide 186. When the slide 130, with the parts carried thereby, has been returned to its outer position, the cam plate 205 engages the roller. 204-and swings the lever 202 downward. The hook memher 208 engages the ledge 201 and pulls the slide downward, thus closing the cutter heads. When the cutters are restored to normal position the plunger 187 snaps into engagement with the slide 186, thus locking the slide in position. Then the cam member 206 restores the lever 202 to the position shown in Fig. 7. Y

It will be understood that the opening 30 of the cutter heads and the return movement of the slide 130 and the subsequent closing of the cutter heads take place simultaneously with the supplying and discharging of blanks and the indexing of the 35 turret. WVhen all of these operations have been performed, the shaft 25 having made a complete revolution, is stopped in the way already described. Just before the shaft stops the tappet 156 engages the pin 155 to start the movement of the slide 130 in the threading direction, as described. At the end of the threading operation the shaft 25 is again started, as described, and these movements are repeated indefinitely.

What I claim is:

1. The combination of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively. to predetermined stations, cutting tools adapted to engage blanks carried by the spindles, a magazine mechanism comprising runways having a side wall inclined at 45 and a bottom wall oppositely inclined at 45 whereby the lowermost blank, regardless of diameter, is held with its axis in a fixed vertical plane which includes the spindle axis at one station, and means for bodily moving the magazine mechanism vertically 110 to bring the axis of the lowermost blank into alinement with the spindle at the said station.

2. The combination of a rotatable turret head, rotatable blank-carrying .spindles 15 mounted in the turret head, means for indexing the head to bring the spindle respectively to predetermined stations, cutting tools adapted to engage blanks carried by the spindles, a magazine mechanism for holding a plurality of blanks of which the lowermost is in alinement with the spindle at one station, a reciprocating rod for successively moving the lowermost blanks longitudinally into the respectively adjacent spindles, stops in the spindles for limiting the inward movements of the blanks, a finger adapted to be pushed between each lowermost blank and the next blank to support the latter while the lowermost blank is being moved into the spindle, and a cam movable with the reciprocating rod and serving to move the finger into and out of operative position.

3. The combination of a rotatable turret head, rotatable blank-carrying spindles mounted in the turrethead, means for in-- dexing the head to bring the spindles respectively to predetermined stations, cutting tools adaptedto engage blanks carried by the spindles, a magazine mechanism for holding a blank in alinement with the spindle at the supply station, means for effecting relative movement between the blanks and the respectively adjacent spindles in order that the former may be engaged by the latter, movable stops. in the spindles for determining the positions of the blanks therein, and means at the supply station supported independently of the turret head for successively determining the position of the stops.

4. The combination of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, cutting tools adapted to engage blanks carried by the spindles, a magazine mechanism for holding a blank in alinement with the spindle at the supply station, means for successively moving the blanks longitudinally into the respectively adjacent spindles, movable stops in the spindles for limiting the inward movements of the blanks, and means at the supply station supported independently ot the turret head for successively determining the position of the stops.

5. The combination of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, cutting tools adapted to engage blanks carried by the spindles, a magazine mechanism for holding a blank in alinement with the spindle at the supply station, means for successively moving the blanks longitudinally into the respectively adjacent spindles, movable stops in the spindles for limiting the inward movements of the blanks, and an actuating rod at the supply station movable successively into the spindles at the outer ends thereof to engage and determine the position of the stops.

6. The combination of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret 'head, means for indexing the head to bring the spindles respectively to predetermined stations, cutting tools adapted to engage blanks carried by the spindles, a magazine mechanism for holding a blank in alinement with the spindle at the supply station, means for effectingrrelative movement between the blanks I head,

and the respectively adjacent spindles in order that the former may be engaged by the latter, movable stops in the spindles for determining .the positions of the blanks therein, and means at the discharge'station for moving the stops to eject finished blanks.

7. The combination of a rotatable turret head,. rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, cutting tools adapted to engage blanks carried by the spindles, a magazine mechanism for holding a blank in alinement with the spindle at the supply station, means for successively movingthe blanks longitudinally into the respectively adjacent spindles, movable stops in the spindles for limiting the inward movements of the blanks, and means at the discharge station for moving the stops to eject finished blanks.

8. The combination of a rotatable turret rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles re-- spectively to predetermined stations, cutting tools adapted to engage blanks carried by the spindles, a magazine mechanism for.

holding a blank in alinement with the spindle at the supply station, means ,for successively moving the blanks longitudinally into therespectively adjacent spindles, movable stops in the spindles for limiting the inward movements of the blanks, means at the supply station supported independently of t e turret head for successively determining the position of the stops, and means at the dlscharge station for moving the sto s to eject finished blanks.

9. T e combination of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, cutting tools adapted to engage blanks carried by the spindles, a magazine mechanism for holding a blank in alinement with the spindle at the supply station, means for successively moving the blanks longitudinally into the respectively adjacent spindles, movable stops in the spindles for limiting the inward movements of the blanks, an actuating rodat the supply station movable successively into the spindles at the outer ends thereof to engage and determine the position of the stops, and an actuating rod "at the discharge station movable successively ret head, rotatable blank-carrying spindles mounted in the turret head, means for indexingv the head to bring the spindles respectively to predetermined stations, cutting 18 0 rod at the supply station movable succeshead,

sively into the spindles'at the outer ends thereof to engage and determine the position of the stops, an actuating rod atthe discharge station movable successively into the spindles at the outer ends thereof to en gage the stops and move them to eject ished blanks, and a single slide carrying the two actuating rods.

11.. The combination of a rotatable turret rotatable blank-carrying spindles mounted in the turret head and provided with chucks, means for indexing the head to bring the spindles respectively to predetermined stations, cutting tools adapted to engage blanks carried by the spindles, a magazine mechanism for holding a blank in alinement with the spindle at thesupply station, means for successively moving the blanks longitudinally into the respectlvely adjacent chucks, movable stops in the spindles for limiting the inward movements of the blanks, means at the discharge sta tion for moving the stops to eject finished blanks, and means for simultaneously opening the chucks at the discharge and supply stations to permit the discharge of a finished blank and the supplying of a new blank and for thereafter simultaneously closing the said chucks.

12. The combination of a rotatable turret head, "rotatable blank-carrying spindles mounted in the turret head and provided with chucks, means for indexing the head to bring the spindles respectively to predetermined stations, cutting tools ada ted to engage blanks carried by the spind es, a magazine mechanism for holding a blank in alinement with the spindle at the supply station, means for successively moving the blanks longitudinally into the respectively adjacent chucks, movable stops in the splndles for limiting the inward movement of the blanks, an actuating rod at the supply station movable successively into the spindles at the outer ends thereof to engage and determine the position of the stops, an actuating rod at the discharge station movable successively into the spindles at the outer ends thereof to engage the stops and move them to eject finished blanks, a bracket having a horizontal guideway, a slide in the guidewa carrying the two actuating rods, a secon slide in the guideway, and means carried by the second slide for simultaneously opening the chucks at the discharge and supply stations to permit the discharge \i for simultaneously adjusting the two sets of tools inward or outward.

14L. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, two sets of threading tools respectively positioned to engage the blanks at successive stations, means for supporting the two sets of tools and for feeding them in unison, and means for simultaneously adjusting the two sets of tools inward or outward, the said means comprising gears. connected with the heads and longitudinal toothed members meshing with the gears.

15. The combination in a threading machine, of a rotatable blank-carrying spindle, a set of threading tools positioned to engage the blank, a worm wheel connected with the threading tools to move them inward or outward, a rotatable worm meshing with the worm wheel, and means 'for bodily moving the worm longitudinally.

16. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, two sets of threading tools respectively positioned to engage the blanks at successive stations, means for supporting the two sets of tools and for feeding them in unison, and means for simultaneously adjusting the two sets of tools inward or outward, the said means comprising worm wheels connected with the heads and longitudinally movable wormsmeshing with theworm wheels.

17. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, two sets of threading tools respectively positioned to engage the blanks at successive stations, means for supporting the two sets of tools and for feeding them in unison, and means for simultaneously adjusting the two sets of tools inward or outward, the said means comprising worm wheels connected with the heads and longitudinally movable independently rotatable worms meshing with the worm wheels.

18. The combination in a threading machine, of a. rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, two sets of threading tools respectively positioned to engage the blanks at successive stations, means for supporting the two sets of tools and for feeding them in unison, means for simultaneously adjusting the two sets of tools inward or outward, the said means comprising gears connected with the heads and longitudinal toothed members meshing with the gears, a spring for moving the toothed members in one di-' rection to move the tools outward, a releasable latch normally preventing such movement, means for releasing the latch, and means for subsequently moving the toothed members in the other direction to move the tools inward.

19. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, two sets of threading tools respectively positioned to engage theblanks at successive stations, means for supporting the two sets of tools and for feeding them in unison, and means for moving the tools slightly inward during cutting to form a taper on the blanks.

20. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, two sets of threading tools respectively positioned to engage the blanks at successive stations, means for sup orting the two sets of tools and moving t em in 5 unison, a slide connected with the tools for' moving them outward or inward, a second slide carrying the first slide and movable parallelly therewith, and means for moving the first slide independently of the second slide or for moving both slides together to move the tools outward or inward.

21. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, means for indexing the head to bring the spindles respectively to predetermined stations, two-sets of threading tools respectively positioned to engage the blanks at successive stations, means for supporting the two sets of tools and moving them in unison, a slide connected with the tools for moving them outward or inward, a second slide carrying the first slide and movable parallelly therewith, a spring formoving the first slide relatively to the second slide,

a releasable latch normally preventing relative movement between the slides, means for releasing the latch to permit the first slide to move the tools outward, means for subsequently moving the first slide in opposition to the spring to move "the tools inward, and means for moving both slides together in the last said direction during cutting to move the tools inward.

22. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, driving mechanism for the spindles, means for indexing the head to bring the spindles respectively to predetermined stations, a threading tool positioned to engage the blanks at one of the stations, and feeding mechanism for the threading tool directly and positively connecting the said tool with the aforesaid driving mechanism, whereby the feeding is effected in accurately timed relation with the spindle rotation.

23. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, driving mechanism for the spindles comprising a shaft extending through the center of the turret, means for indexing the head to bring the spindles respectively, to predetermined stations, a threading tool positioned to engage the blanks at one of the stations, and feeding mechanism for the threading tool directly and positively connecting the said tool with the aforesaid shaft, whereby the feeding is efiected in accurately timed relation with the spindle r0- tation.

24. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, driving mechanism for the spindles, means for indexing the head to brin the spindles respectively to predetermine stations, two sets of threading tools respectively positioned to engage the blanks at successive stations, means for supporting the two sets of tools, and feeding mechanism for the tools directly and positively connecting the said tools with the aforesaid driving mechanism, whereby the feeding is effected in accurately timed relation with the spindle rotation.

25. The combination in a threading machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, driving mechanism for the spindles comprising a shaft extending through the center of the turret, means for indexing the head to bring the spindles respectively to predetermined stations, two sets of threading tools respectively positioned to engage the blanks at successive stations, means for supporting the two sets of tools, and feed ing mechanism for the tools directly and positively connecting the said tools with the aforesaid shaft, whereby the feeding is effected in accurately timed relation with the spindle rotation.

26. The combination in a metal cutting machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, driving mechanism for the spindles, means for indexing the head to bring the spindles respectively to predetermined stations, cutting tools positioned to engage the blanks at successive stations, a support for the tools, means including a screw connected with the aforesaid driving mechanism for moving the support in the feeding direction in accurately timed relation with the spindle rotation, and other means for moving the support in the return direction.

27. The combination in a metal cutting machine, of a rotatable turret head, rotatable blank-carrying spindles mounted in the turret head, driving mechanism for the spindles, means for supplying new blanks, for discharging finished blanks and for indexing the head to bring the spindles respectively to predetermined stations, cutting tools positioned to engage the blanks at successive stations, a support for the tools,-

means connected with the aforesaid driving mechanism for moving the support in the feeding direction, means whereby the supplying discharging and indexing means stops itself and starts the operation of the feeding means, and means whereby the feeding means stops itself and starts the operation of the supplying discharging and indexing means.

In testimony whereof, I hereto aflix my signature.

FRIEDERICH MULLER. 

